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Published on: October 5, 2012
Functional linkage between NOXA and Bim in mitochondrial apoptotic events
Jie Han1, Leslie A Goldstein, Wen Hou
1Department of Pathology, University of Pittsburgh School of Medicine, PA 15213, USA.
The Journal of Biological Chemistry
|March 22, 2007
Summary
NOXA protein binding to Mcl-1 displaces Bim, enhancing UV-induced cell death. This NOXA-Bim interaction, mediated by Mcl-1, is crucial for mitochondrial depolarization during apoptosis.
Area of Science:
- Molecular Biology
- Cell Biology
- Apoptosis Research
Background:
- NOXA is a BH3-only protein induced by apoptotic stimuli.
- Both NOXA and Bim bind Mcl-1, but their functional linkage is unknown.
Purpose of the Study:
- To investigate the functional linkage between NOXA and Bim.
- To elucidate the role of Mcl-1 in NOXA-Bim interaction during apoptosis.
Main Methods:
- Studied Mcl-1 binding of endogenous NOXA and Bim.
- Assessed cellular UV sensitivity and mitochondrial depolarization.
- Utilized Bim knockdown to investigate NOXA's effect.
Main Results:
- Endogenous NOXA binding to Mcl-1 displaces Bim.
- Induced NOXA significantly increases UV sensitivity.
- Bim knockdown abrogates NOXA-induced mitochondrial depolarization.
Conclusions:
- NOXA and Bim functionally interact via Mcl-1.
- This Mcl-1-mediated crosstalk is upstream of Bak/Bax activation.
- Endogenous Bim executes the mitochondrial response to NOXA induction.
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